ELISA question

Thanks to everybody for their replies. You have given me a number of
things to try. Another correspondent pointed me to the following site
which has some interesting articles pertaining to this subject (using
their products, of course):
http://nunc.nalgenunc.com/resource/technical/immunology.html
* Robert (BJ) Allan *
* University of British Columbia, Vancouver, BC *
* "My suspicion is that the universe is not only queerer than we *
* suppose, but queerer than we can suppose." J.B.S. Haldane *